The empty casing of a U.S. B-61 nuclear gravity bomb, shown on display in 2005 at a museum in Las Vegas. A new Pentagon analysis says the National Nuclear Security Administration has underestimated the cost and schedule for modernizing the weapon (AP Photo/Joe Cavaretta).

Completing planned updates to the U.S. stockpile of B-61 nuclear gravity bombs would require the Sandia National Laboratories in New Mexico to carry out significantly more engineering activities than the National Nuclear Security Administration has acknowledged, an oversight responsible in large part for the agency's incorrectly low projection of the effort's expense, according to U.S. Defense Department findings reported by the Albuquerque Journal on Sunday.

Staffing demands for B-61 modernization activities would probably necessitate more than the 600 specialists anticipated by the Sandia laboratory, according to an abstract of findings by the Defense Department's Cost Assessment and Program Evaluation office. The National Nuclear Security Administration -- a semiautonomous branch of the Energy Department -- has not described how it would provide additional specialists to update the bomb's schematics and assemble the altered weapon with new parts, the CAPE office indicated.

A 2010 NNSA estimate placed at $3.9 billion the expense of extending the lives of the decades-old tactical armaments, thought by nongovernmental analysts to number around 400. The agency's projection reached $6.8 billion by July, and the Defense Department later suggested the price tag would rise to $10.4 billion and the program time line would increase by 36 months.

Plans to update and reproduce almost every interior B-61 part are a large, unnecessary contributor to the initiative's projected expense, according to detractors of the effort.

One-time Sandia laboratory vice president Bob Peurifoy said there are no indications of any necessity for steps now being taken to rebuild the 29 key elements that almost constitute the weapon in its entirety. The CAPE assessment does not address the necessity for the intended revisions.

“We’ve worked with CAPE to study how we meet the requirements for the B-61 while ensuring that we’re being responsible stewards of taxpayer dollars,” NNSA spokesman Josh McConaha told the Journal in prepared remarks.

“We’re currently doing the required engineering and design work on the B-61 which will allow us to make key decisions that we can then use to inform a well-researched and validated cost baseline," the spokesman said. "All of the information we’ve gathered, including the CAPE study, will help us check any final conclusions against a long list of variables so that we’re certain we have a cost baseline that is as accurate as possible.”

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